Coatings and sealants used in the aerospace industry must meet demanding performance requirements. The coatings and sealants must exhibit excellent initial adhesion, tensile strength and elongation and must maintain acceptably high values following exposure to aviation fluids, high temperature, and/or salt spray. In addition, to reduce the weight of aerospace vehicles it is also desirable that aerospace coatings and sealants exhibit a low specific gravity.
Aerospace compositions having a low specific gravity can include a high loading of low density filler. The addition of a high volume or weight percent of a low density filler can increase the viscosity of the uncured composition to an extent that the ability to apply the composition and/or the useful working time of the composition is not acceptable. To provide homogeneous properties, it is also important that a filler be uniformly dispersed throughout the coating or sealant.
Low density aerospace coatings and sealants having homogenously dispersed fillers, improved adhesion, and enhanced flexibility are desired.